Felix Hilpert

Bevacizumab May Differentially Improve Prognosis of Advanced Ovarian Cancer Patients with Low Expression of VEGF-A165b, an Antiangiogenic VEGF-A Splice Variant

Abstract Purpose: The identification of a robust IHC marker to predict the response to antiangiogenic bevacizumab in ovarian cancer is of high clinical interest. VEGF-A, the molecular target of bevacizumab, is expressed as multiple isoforms with pro- or antiangiogenic properties, of which VEGF-A165b is the most dominant antiangiogenic isoform. The balance of VEGF-A isoforms is closely related to the angiogenic capacity of a tumor and may define its vulnerability to antiangiogenic therapy. We investigated whether the expression of VEGF-A165b could be related to the effect of bevacizumab in advanced ovarian cancer patients. Experimental Design: Formalin-fixed paraffin-embedded tissues from 413 patients of the ICON7 multicenter phase III trial, treated with standard platinum-based chemotherapy with or without bevacizumab, were probed for VEGF-A165b expression by IHC. Results: In patients with low VEGF-A165b expression, the addition of bevacizumab to standard platinum-based chemotherapy significantly improved progression-free (HR: 0.727; 95% CI, 0.538–0.984; P = 0.039) and overall survival (HR: 0.662; 95% CI, 0.458–0.958; P = 0.029). Multivariate analysis showed that the addition of bevacizumab in low VEGF-A165b–expressing patients conferred significant improvements in progression-free survival (HR: 0.610; 95% CI, 0.446–0.834; P = 0.002) and overall survival (HR: 0.527; 95% CI, 0.359–0.775; P = 0.001), independently from established risk factors. Conclusions: We demonstrate for the first time that bevacizumab may differentially improve the prognosis of advanced ovarian cancer patients with low expression of VEGF-A165b, an antiangiogenic VEGF-A splice variant. We envision that this novel biomarker could be implemented into routine diagnostics and may have direct clinical implications for guiding bevacizumab-related treatment decisions in advanced ovarian cancer patients.

Molecular Results and Potential Biomarkers Identified from the Phase 3 MILO/ENGOT-ov11 Study of Binimetinib versus Physician Choice of Chemotherapy in Recurrent Low-Grade Serous Ovarian Cancer

Abstract Purpose: We present the results of a post hoc tumor tissue analysis from the phase 3 MILO/ENGOT-ov11 study (NCT01849874). Patients and Methods: Mutation/copy-number analysis was performed on tissue obtained pre-randomization. The Kaplan–Meier method was used to estimate progression-free survival (PFS). Unbiased univariate analysis, Cox regression, and binary logistic regression were used to test associations between mutation status and outcomes, including PFS and binary response by local RECIST 1.1. Results: MILO/ENGOT-ov11 enrolled 341 patients, ranging in age from 22 to 79, from June, 2013 to April, 2016. Patients were randomized 2:1 to binimetinib or physician's choice of chemotherapy (PCC). The most commonly altered gene was KRAS (33%). In 135 patients treated with binimetinib with response rate (RR) data, other detected MAPK pathway alterations included: NRAS (n = 11, 8.1%), BRAF V600E (n = 8, 5.9%), RAF1 (n = 2, 1.5%), and NF1 (n = 7, 5.2%). In those with and without MAPK pathway alterations, the RRs with binimetinib were 41% and 13%, respectively. PFS was significantly longer in patients with, compared with those without, MAPK pathway alterations treated with binimetinib [HR, 0.5; 95% confidence interval (CI) 0.31–0.79]. There was a nonsignificant trend toward PFS improvement in PCC-treated patients with MAPK pathway alterations compared with those without (HR, 0.82; 95% CI, 0.43–1.59). Conclusions: Although this hypothesis-generating analysis is limited by multiple testing, higher RRs and longer PFS were seen in patients with low-grade serous ovarian cancer (LGSOC) treated with binimetinib, and to a lesser extent in those treated with PCC, who harbored MAPK pathway alterations. Somatic tumor testing should be routinely considered in patients with LGSOC and used as a future stratification factor.

A Study of MEK162 vs. Physician's Choice Chemotherapy in Patients With Low-grade Serous Ovarian, Fallopian Tube or Peritoneal Cancer

The MILO Study (MEK Inhibitor in Low-grade Serous Ovarian Cancer) is a Phase 3 study during which patients with recurrent or persistent low-grade serous (LGS) carcinomas of the ovary, fallopian tube or primary peritoneum will receive either investigational study drug MEK162 or a chemotherapy chosen by the physician (liposomal doxorubicin, paclitaxel or topotecan). Patients will be followed to compare the effectiveness of the study drug to that of the selected chemotherapies. Patients may be eligible to crossover from physician's choice chemotherapy to MEK162 if they meet certain inclusion criteria including centrally confirmed disease progression. Approximately 360 patients from North America, Europe and Australia will be enrolled in this study.